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Compound Deep-Dive

Tier 1: MainstreamBest used as an 'anti-catabolic' insurance policy during aggressive weight loss or for beginners.

HMB

Beta-Hydroxy Beta-Methylbutyrateβ-Hydroxy β-MethylbutyrateCalcium HMBHMB Free Acid

Effective for muscle preservation

Hype Risk

6/10

Noticeability

3/10

Evidence Tier

Moderate

Cost / Month

~$14

Overhyped for mass

What it's actually good for

Muscle

Research Supported

Highly effective for preventing muscle loss during inactivity or aggressive calorie deficits.

Recovery

Mixed Evidence

May reduce markers of muscle damage, though performance recovery benefits vary among trained athletes.

Energy: neutralFocus: neutralSleep: neutralLongevity: neutralMood: neutralImmunity: neutral

How it works

HMB is a metabolite of the amino acid leucine that primarily functions to reduce muscle protein breakdown. It is most effective for preserving muscle mass during periods of high stress, calorie restriction, or in individuals new to resistance training.

It inhibits the ubiquitin-proteasome pathway to decrease muscle protein breakdown and may stimulate the mTOR pathway to support protein synthesis.

Safety

  • Generally well-tolerated in human studies at standard doses.
  • No significant adverse effects reported in long-term clinical trials.

The full StackRoast report adds

  • The exact dose, timing, and effective range to actually run it at
  • Where people go wrong with it — the dose-creep and timing traps
  • What HMB clashes with or duplicates in your stack
  • Which brands are actually worth buying
Roast My Stack →

Community Reality Check

Distilled from 450 threads
Confidence: high

What users report

  • Muscle retention during calorie deficits
  • Reduced muscle soreness

The catch

  • Lack of noticeable size gains
  • High price point

Side effects reported

  • None commonly reported
https://www.reddit.com/r/Supplementshttps://www.reddit.com/r/Fitness

The Receipts

8 sources— studies, videos & links

Taking HMB in a stack? Find out if the combination actually makes sense.

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